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Perinatal risks of planned home births in the United States Amos Gru¨nebaum, MD; Laurence B. McCullough, PhD; Robert L. Brent, MD, PhD, DSc (Hon); Birgit Arabin, MD; Malcolm I. Levene, MD, FRCP, FRCPH; Frank A. Chervenak, MD OBJECTIVE: We analyzed the perinatal risks of midwife-attended
planned home births in the United States from 2010 through 2012 and compared them with recommendations from the American College of Obstetricians and Gynecologists (ACOG) and the American Academy of Pediatrics (AAP) for planned home births. STUDY DESIGN: Data from the US Centers for Disease Control and
Prevention’s National Center for Health Statistics birth certificate data files from 2010 through 2012 were utilized to analyze the frequency of certain perinatal risk factors that were associated with planned midwife-attended home births in the United States and compare them with deliveries performed in the hospital by certified nurse midwives. Home birth deliveries attended by others were excluded; only planned home births attended by midwives were included. Hospital deliveries attended by certified nurse midwives served as the reference. Perinatal risk factors were those established by ACOG and AAP. RESULTS: Midwife-attended planned home births in the United States had the following risk factors: breech presentation, 0.74% (odds ratio [OR], 3.19; 95% confidence interval [CI], 2.87e3.56); prior cesarean
delivery, 4.4% (OR, 2.08; 95% CI, 2.0e2.17); twins, 0.64% (OR, 2.06; 95% CI, 1.84e2.31); and gestational age 41 weeks or longer, 28.19% (OR, 1.71; 95% CI, 1.68e1.74). All 4 perinatal risk factors were significantly higher among midwife-attended planned home births when compared with certified nurse midwiveseattended hospital births, and 3 of 4 perinatal risk factors were significantly higher in planned home births attended by noneAmerican Midwifery Certification Board (AMCB)ecertified midwives (other midwives) when compared with home births attended by certified nurse midwives. Among midwife-attended planned home births, 65.7% of midwives did not meet the ACOG and AAP recommendations for certification by the American Midwifery Certification Board. CONCLUSION: At least 30% of midwife-attended planned home births
are not low risk and not within clinical criteria set by ACOG and AAP, and 65.7% of planned home births in the United States are attended by non-AMCB certified midwives, even though both AAP and ACOG state that only AMCB-certified midwives should attend home births. Key words: home birth, midwives, perinatal risks
Cite this article as: Gru¨nebaum A, McCullough LB, Brent RL, et al. Perinatal risks of planned home births in the United States. Am J Obstet Gynecol 2015;212:350.e1-6.
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here has been an increase in home births in the United States over the last 10 years.1 Recent studies have shown that when compared with hospital births, planned home births by midwives are associated with an increase in adverse neonatal outcomes, such as neonatal deaths,2-4 Apgar score of 0, neonatal seizures, or serious neurological dysfunction.5 The American College of Obstetricians and Gynecologists (ACOG) and
the American Academy of Pediatrics (AAP) have concluded that planned hospital births are safer than planned home births, and both professional organizations have also identified clinical criteria for selecting low-risk patients for planned home births.6,7 ACOG and AAP have also stated that midwives attending planned home births should be certified by the American Midwifery Certification Board (AMCB).6,7
From the Department of Obstetrics and Gynecology, Weill Medical College of Cornell University, New York, NY (Drs Grünebaum, Brent, and Chervenak); Center for Medical Ethics and Health Policy, Baylor College of Medicine, Houston, TX (Dr McCullough); Departments of Obstetrics and Gynecology, Thomas Jefferson University, Philadelphia, PA, and Alfred I. DuPont Hospital for Children, Wilmington, DE (Dr Brent); Center for Mother and Child, Philipps University, Marburg, and Clara Angela Foundation, Berlin, Germany (Dr Arabin); and Division of Pediatrics and Child Health, University of Leeds, Leeds, England, UK (Dr Levene). Received Aug. 29, 2014; revised Sept. 9, 2014; accepted Oct. 13, 2014. The authors report no conflict of interest. Corresponding author: Amos Grünebaum, MD. [email protected] 0002-9378/$36.00 ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajog.2014.10.021
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The purpose of this study was to evaluate the frequency of certain perinatal risk factors that were associated with planned midwife-attended home births in the United States from 2010 through 2012 and to compare them with clinical criteria for planned home births established by the ACOG and AAP.
M ATERIALS
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We utilized data from the National Center for Health Statistics of the US Centers for Disease Control and Prevention (CDC) birth certificate data for 2010e2012, the most recent data available to analyze the 4 ACOG/AAP clinical criteria for planned home births. The CDC files contain detailed information on each of the approximately 4 million births in the United States each year. Data on patient characteristics including birth setting, method of delivery, birth attendant, gestational age, infant birthweight, maternal age, history of
ajog.org prior cesarean delivery, and parity are reported on birth certificates filed each year with each of the states in the United States and compiled by National Center for Health Statistics. These data are publicly accessible on the Internet (http://205.207.175.93/vitalstats/Report Folders/ReportFolders.aspx), where detailed tables can be created and downloaded for further evaluation. According to CDC data, “almost all the home births attended by certified nurse-midwives ⁄certified midwives (98%) or “other” midwives (99%) were planned,”8,9 and therefore, we defined planned home births as births attended at home by midwives. We excluded from planned home births those performed at home by others (eg, family members, emergency medical service, or police, taxi drivers as well as unattended births). Planned US midwife home deliveries for the years 2010e2012, the most recent years available, were analyzed for ACOG and AAP perinatal risk factors that should be excluded from home births7: vaginal breech deliveries, prior cesarean delivery, twin gestations, and postdate pregnancies (gestational age 41 weeks or longer). Hospital births attended by certified nurse midwives served as a reference. Home birtheplanned midwife-attended deliveries were compared with hospital-certified nurse midwives (CNM)eattended deliveries. The CDC database separates midwives into CNM and other midwives. The AMCB certifies 2 kinds of midwives: CNMs and certified midwives (CMs), both of whom have graduated from a midwifery education program accredited by the American Commission for Midwifery Education. The total number of AMCB-certified midwives (CNMs plus CMs) includes only a small percentage of CMs because CMs are permitted to practice in only 5 states. Therefore, the CDC designation of CNMs captures nearly all of AMCBcertified midwives. In addition to CNMs, the CDC also has a designation of other midwives, which includes certified professional midwives, who are not eligible for certification by the AMCB and who have no requirement of a Bachelor’s degree or
Obstetrics graduate training. In addition, the CDC designation of other midwives may include lay midwives and others without any graduate midwifery training. We performed a subanalysis and compared the frequency with which certain perinatal risk factors were associated with home births attended by CNMs with those attended by other midwives (ie, midwives not eligible to get certified by the AMCB). Data were abstracted from the US birth certificate data. Because nonidentifiable data from a publicly available data set were used, this study was not considered human subject research and did not require review by the Institutional Review Board of Weill Medical College of Cornell University. Statistical analyses were conducted for comparisons between planned midwife-attended home births and CNM-attended deliveries in the hospital. Odds ratios and 95% confidence intervals were calculated for each of the 3 provider groups (CNM-attended home birth, other midwife-attended home birth, and CNM-attended hospital birth) and 4 of the risk groups. All statistical analyses were conducted in OpenEpi.10
R ESULTS Between 2010 and 2012, there were a total of 11,905,817 deliveries in the United States, of which 736,070 were attended by CNMs in the hospital. There were 85,318 home births (0.71% of all births in the United States) and after exclusion of 29,178 home birth deliveries performed by others, we included 56,140 deliveries that were attended by midwives at home and are considered planned midwife-attended home births. CNMs attended 19,263 (34.3%) of these home births, whereas other midwives attended 36,877 (65.7%) of planned home births. Table 1 shows the comparisons of perinatal risk factors between deliveries attended in the hospital by CNMs and planned midwife-attended home births by CNMs and other midwives. Of the midwife-attended planned home births, approximately 3 in 10 were at a gestation of 41 weeks or longer, 1 in 156 were
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births with twins, approximately 1 in 23 were vaginal births after cesarean deliveries, and 1 in 135 home births were births with breech presentation. Planned home births attended by CNMs and other midwives had a significantly higher frequency of certain perinatal risks when compared with CNM-attended hospital births. Planned home births attended by noneAMCBcertified other midwives had a significantly higher frequency of perinatal risks for breech presentation, prior cesarean deliveries, and twins, when compared with planned home births attended by CNMs.
C OMMENT The AAP and ACOG previously published policy statements on planned home birth with recommendations when to consider planned home birth, and they listed the use of strict selection criteria for planned home births (Tables 2 and 3).6,7 According to the ACOG, selection criteria for home births include singletons, cephalic pregnancies between 37 and 41 weeks, no prior cesarean deliveries, and certified midwives or physicians as birth attendants. This study shows that 1 in 156 of midwife-attended planned home births (0.64%) were twin pregnancies, even though the ACOG considers twins a contraindication for home births because there is no adequate fetal monitoring, no experienced team, and no ultrasound available in home births.6,7 Studies on the safety of home births from Canada, England, and The Netherlands excluded twins as candidates for home birth because of increased risks.11-14 Even within hospitals, delivery of the second twin, especially when not engaged or nonvertex, requires an experienced obstetrician to prevent perinatal morbidity or even mortality.15 We note that our data indicate that in some hospitals there were apparently CNM deliveries of twin and breech-presentation pregnancies. The data in this study show that 1 in 135 of planned home births attended by midwives (0.74%) were vaginal breech deliveries. Breech vaginal birth is associated with significantly increased risks.
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1.08 (1.01e1.14)
1.03 (0.99e1.06)
1.44 (1.39e1.5)
1.73 (1.69e1.77)
1.34 (1.28e1.41)
1.67 (1.62e1.73)
1.41 (1.37e1.45)
1.71 (1.68e1.74)
9.73 (3567) 9.08 (1744) 6.91 (50,848) Postdates 42 wks
27.7 (5320)
CI, confidence interval; CNM, certified nurse midwife; MW, midwife; OR, odds ratio.
18.59 (136,729) Postdates 41 wks
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9.5 (5311)
28.19 (15,755) 28.45 (10,435)
1.33 (1.05e1.67) 2.25 (1.98e2.57) 1.7 (1.39e2.08) 2.06 (1.84e2.31) 0.64 (357) 0.52 (101) 0.31 (2276) Twins
0.69 (256)
1.15 (1.06e1.26) 2.25 (2.14e2.37) 1.93 (1.8e2.08) 2.08 (2.0e2.17) 4.4 (2463) Prior cesarean delivery
3.99 (767) 2.11 (15,455)
Vaginal breech
4.6 (1696)
3.49 (3.08e3.94) 2.64 (2.19e3.18) 3.19 (2.87e3.56) 0.74 (416) 0.23 (1716)
Risk factor
0.61 (118)
CNM-attended (n [ 736,070), % (n)
0.81 (298)
Other MWattended home births vs CNMattended hospital births, OR (95% CI) CNM-attended home births vs CNM-attended hospital births, OR (95% CI) MW-attended home births vs CNM-attended hospital births, OR (95% CI) All MWattended (n [ 56,140), % (n) CNMattended (n [ 19,263), % (n)
Other MWattended (n [ 36,877), % (n) Home births Hospital births
Perinatal risk factors: CNM-attended hospital births vs midwife-attended home births
TABLE 1
1.32 (1.07e1.64)
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Other MWattended home births vs CNMattended home births, OR (95% CI)
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Since the publication of the Term Breech Trial, clinical practices changed around the world, increasing cesarean deliveries for breech births.16 The ACOG recommends that planned vaginal breech births should be done only under hospital-specific protocol guidelines.17 Azria et al18 recommended that a trial for vaginal births in breech presentations should be attempted only with continuous electronic fetal heart rate monitoring and the presence of ultrasound during labor and delivery. Neither electronic fetal heart rate monitoring nor ultrasound is available in home births. Janssen et al11 from Canada and the Home Birth in England Study12 excluded breech presentations from their home birth eligibility requirements. Therefore, it is not surprising that the Midwives Alliance of North America study of planned home births reported an intrapartum death rate of 13.51 per 1000 and a 9.16 per 1000 neonatal mortality rate in breech presentations.19 When compared with the neonatal death rates from hospital deliveries,2-4 these adverse neonatal outcomes are significantly increased. The ACOG and AAP criteria for home births specifically exclude pregnancies 41 weeks or longer from their home birth eligibility.6,7 In this study, 28.19% of home births were 41 weeks or longer. Postterm pregnancies are associated with multiple, well-known complications, such as labor dystocia, increased perinatal mortality rate, low umbilical artery pH levels at delivery, low 5 minute Apgar scores, postmaturity syndrome, fetal distress, cephalo-pelvic disproportion, postpartum hemorrhage, and an increased risk of neonatal death within the first year of life.20,21 A trial of labor after prior cesarean delivery (TOLAC) is associated with a greater perinatal risk than is elective repeat cesarean delivery without labor. TOLACs have an overall small but significantly increased risk of uterine rupture with often catastrophic consequences to mother and/or fetus.22,23 This study showed that nearly 1 in 23 midwife-attended home births (n ¼ 2463, 4.4%) had a home vaginal birth after prior cesarean delivery (VBAC) in
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TABLE 2
Planned home birth: recommendations when considering planned home birth Candidates for home delivery Absence of preexisting maternal disease Absence of significant disease occurring during the pregnancy A singleton fetus estimated to be appropriate for gestational age A cephalic presentation A gestation of 37 to less than 41 completed weeks of pregnancy Labor that is spontaneous or induced as an outpatient A mother who has not been referred from another hospital Systems needed to support planned home birth The availability of a certified nurse midwife, certified midwife, or physician practicing within an integrated and regulated health system Attendance by at least 1 appropriately trained individual (see text) whose primary responsibility is the care of the newborn infant Ready access to consultation Assurance of safe and timely transport to a nearby hospital with a preexisting arrangement for such transfers Adapted from American Academy of Pediatrics.6 Grünebaum. Perinatal risks of planned US home births. Am J Obstet Gynecol 2015.
spite of the fact that ACOG considers prior cesarean section an absolute contraindication to planned home birth.7 TOLACs at home births are even more worrisome, considering the increase in VBACs in home births.24 The recent Midwives Alliance of North America study showed a very high 2.85 per 1000 intrapartum fetal death rate with VBACs.19 The ACOG and AAP recommend that only midwives certified by the AMCB should attend home births.6,7 Nevertheless, this study shows that approximately 2 of 3 planned home births were performed by non-AMCB-certified midwives. Professional organizations like the ACOG and AAP should respond to these findings by continuing to
support collaborative practices in the hospital between physicians and AMCBcertified midwives and strive for a hospital birth that resembles more closely a home birth environment.25 Selection of patients for home births by countries with midwife organizations, such as the Royal Dutch Organisation of Midwives, follows collaborative guidelines with strict protocols for selecting patients for home births.26 The American College of Nurse Midwives has not established midwife-generated guidelines of patient selection for home births in the United States saying that “. guidelines would impact [midwives’] autonomy” and “guidelines might not support midwives if they choose to attend the home birth of a woman with a
breech presentation or a twin gestation or a woman who desires a trial of labor after a previous cesarean.”27 It is possible that some pregnant women with risk factors may insist on home births despite the increased risks of adverse outcomes. In circumstances in which home births are contraindicated because of risk factors, physicians and midwives have the professional responsibility to strongly recommend for hospital birth, to recommend against home births, and to refuse the woman’s request to attend their home birth. This is because patients’ requests by themselves do not determine professional responsibility.28 Kennare et al29 and Bastian et al30 showed that the increase in neonatal
TABLE 3
ACOG Statement on planned home birth (ACOG 2011) Recent cohort studies reporting lower perinatal mortality rates with planned home birth describe the use of strict selection criteria for appropriate candidates. These criteria include the absence of any preexisting maternal disease, the absence of significant disease arising during the pregnancy, a singleton fetus, a cephalic presentation, gestational age greater than 36 weeks and less than 41 completed weeks of pregnancy, labor that is spontaneous or induced as an outpatient, and that the patient has not been transferred from another referring hospital. Trial of labor after cesarean should be undertaken only in facilities with staff immediately available to provide emergency care. The American College of Obstetricians and Gynecologists’ Committee on Obstetric Practice considers a prior cesarean delivery to be an absolute contraindication to planned home birth. Ready access to consultation and assurance of safe and timely transport to nearby hospitals are critical to reducing perinatal mortality rates and achieving favorable home birth outcomes. Availability of a certified nurse midwife, certified midwife, or physician practicing within an integrated and regulated health system. For quality and safety reasons, the American College of Obstetricians and Gynecologists does not support the provision of care by lay midwives who are not certified by the American Midwifery Certification Board. Adapted from ACOG Committee.7 Grünebaum. Perinatal risks of planned US home births. Am J Obstet Gynecol 2015.
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mortality in planned home births was associated with a poor selection of candidates for home births. Our findings of increased perinatal risks among US midwife-attended planned home births may partially explain reports that show preventable increased adverse outcomes such as increased neonatal mortality rates, low Apgar scores, neonatal seizures, and serious neurological dysfunction among US midwifeattended planned home births.2-5 The strength of this study is that the CDC data are nationally comprehensive. No comparable database exists. A limitation of the results is that the actual number of patients with increased perinatal risks in home births is possibly higher than reported here because patients transferred prior to delivery from a planned home birth to the hospital are counted in the CDC birthing data as hospital births and not home births. Other limitations in this study include concerns that have been expressed about the quality of certain data collected in birth certificates, especially those that address maternal health behaviors or certain medical and obstetric conditions (eg, anemia, gestational diabetes, pregnancy-induced hypertension, concurrent illnesses, congenital anomalies, and comorbidities).31-34 These data elements were not used in our study. Our study used data elements found to be a good source of reliable information in birth certificates and that were validated such as place of births, gestational weeks, presentation, history of prior cesarean delivery, and multiple births.34,35
Conclusion This study demonstrates that many midwife-attended planned home births in the United States do not have low perinatal risks but include readily identifiable prenatal risks such as breech presentation, twins, patients with prior cesarean deliveries, and postdate pregnancies. These risks as well as other perinatal risks are known to be associated with increased adverse birth outcomes and are therefore listed by the ACOG and AAP as contraindications for planned home births. In addition, about two-thirds of planned midwife-attended
home births in the United States are attended by noneAMCB-certified midwives. Our study also shows that planned home births attended by midwives not certified by the AMCB have a higher frequency of perinatal risks than planned home births attended by AMCB-certified nurse midwives. REFERENCES 1. MacDorman MF, Mathews TJ, Declercq E. Trends in out-of-hospital births in the United States, 1990e2012. NCHS Data Brief no. 144, March, 2014. Hyattsville MD: National Center for Health Statistics. 2. Grünebaum A, McCullough LB, Sapra KJ, et al. Early and total neonatal mortality in relation to birth setting in the United States, 2006e2009. Am J Obstet Gynecol 2014;211:390.e1-7. 3. Cheng YW, Snowden JM, King TL, Caughey AB. Selected perinatal outcomes associated with planned home births in the United States. Am J Obstet Gynecol 2013;209: 325.e1-8. 4. Wax JR, Lucas FL, Lamont M, Cartin A, Blackstone J. Maternal and newborn outcomes in planned home birth vs planned hospital births: a metaanalysis. Am J Obstet Gynecol 2010;203: 243.e1-8. 5. Grünebaum A, McCullough LB, Sapra KJ, et al. Apgar score of zero at five minutes and neonatal seizures or serious neurologic dysfunction in relation to birth setting. Am J Obstet Gynecol 2013;209:323.e1-6. 6. American Academy of Pediatrics. Policy statement on planned home birth. Pediatrics 2013;131:1016-20. 7. American College of Obstetricians and Gynecologists. Planned home birth. Committee Opinion no. 476. ACOG Committee on Obstetric Practice. Obstet Gynecol 2011;117(2 Pt 1): 425-8. 8. National Center for Health Statistics. Vital statistics data available online: birth data files. Available at: http://www.cdc.gov/nchs/data_ access/VitalStatsOnline.htm. Accessed Aug. 28, 2014. 9. MacDorman MF, Declerq E, Mathews TJ. United States Home Births Increase 20 Percent from 2004 to 2008. Birth 2011;38:185-90. 10. Dean AG, Sullivan KM, Soe MM. OpenEpi: open source epidemiologic statistics for public health, version 2.3.1. Updated June 23, 2011. Available at: www.OpenEpi.com. Accessed June 1, 2014. 11. Janssen PA, Saxell L, Page LA, Klein MC, Liston RM, Lee SK. Outcomes of planned home birth with registered midwife versus planned hospital birth with midwife or physician. CMAJ 2009;181:377-83. 12. Brocklehurst P, Hardy P, Hollowell J, et al. Perinatal and maternal outcomes by planned place of birth for healthy women with low risk pregnancies: the Birthplace in England national
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prospective cohort study. Birthplace in England Collaborative Group. BMJ 2011;343: d7400. 13. Hutton EK, Reitsma AH, Kaufman K. Outcomes associated with planned home and planned hospital births in low-risk women attended by midwives in Ontario, Canada, 2003e2006: a retrospective cohort study. Birth 2009;36:180-9. 14. Amelink-Verburg MP, Verloove-Vanhorick SP, Hakkenberg RM, Veldhuijzen IM, Bennebroek Gravenhorst J, Buitendijk SE. Evaluation of 280,000 cases in Dutch midwifery practices: a descriptive study. BJOG 2008;115:570-8. 15. Arabin B, Kyvernitakis I. Vaginal delivery of the second nonvertex twin: avoiding a poor outcome when the presenting part is not engaged. Obstet Gynecol 2011;118:950-4. 16. Hannah ME, Hannah WJ, Hewson SA, Hodnett ED, Saigal S, Willan AR. Planned cesarean section versus planned vaginal birth for breech presentation at term: a randomized multicenter trial. Term Breech Trial Collaborative Group. Lancet 2000;356: 1375-83. 17. American College of Obstetricians and Gynecologists. Mode of term singleton breech delivery. Committee Opinion no. 340 (ACOG Committee on Obstetric Practice). Obstet Gynecol 2006;108:235-7. 18. Azria E, Le Meaux JP, Khoshnood B, et al. Factors associated with adverse perinatal outcomes for term breech fetuses with planned vaginal delivery. Am J Obstet Gynecol 2012;207:285.e1-9. 19. Cheyney M, Bovbjerg M, Everson C, Gordon W, Hannibal D, Vedam S. Outcomes of care for 16,924 planned home births in the United States: the Midwives Alliance of North America Statistics Project, 2004 to 2009. J Midwifery Womens Health 2014;59:17-27. 20. Caughey AB, Stotland NE, Washington AE, Escobar GJ. Who is at risk for prolonged and postterm pregnancy? Am J Obstet Gynecol 2009;200:683.e1-5. 21. Caughey AB, Stotland NE, Washington AE, Escobar GJ. Maternal and obstetric complications of pregnancy are associated with increasing gestational age at term. Am J Obstet Gynecol 2007;196:155.e1-6. 22. Landon MB, Hauth JC, Leveno KJ, et al. Maternal and perinatal outcomes associated with a trial of labor after prior cesarean delivery. N Engl J Med 2004;351:2581-9. 23. Chauhan SP, Martin JN Jr, Henrichs CE, Morrison JC, Magann EF. Maternal and perinatal complications with uterine rupture in 142,075 patients who attempted vaginal birth after cesarean delivery: a review of the literature. Am J Obstet Gynecol 2003;189:408-17. 24. MacDorman MF, Declercq E, Mathews TJ, Stotland N. Trends and characteristics of home vaginal birth after cesarean delivery in the United States and selected States. Obstet Gynecol 2012;119:737-44.
ajog.org 25. Chervenak FA, McCullough LB, Brent RL, Levene MI, Arabin B. Planned home birth: the professional responsibility response. Am J Obstet Gynecol 2013;208:31-8. 26. Commissie Verloskunde van het CVZ. Verloskundig vademecum, 2003. Diemen (The Netherlands): College voor Zorgverzekeringen; 2003. 27. Cook E, Avery M, Frisvold M. Formulating evidence-based guidelines for certified nursemidwives and certified midwives attending home births. J Midwifery Womens Health 2014;59:153-9. 28. Chervenak FA, McCullough LB. The professional responsibility model of obstetrical
Obstetrics ethics: avoiding the perils of clashing rights. Am J Obstet Gynecol 2011;205:315.e1-5. 29. Kennare RM, Keirse MJ, Tucker GR, Chan AC. Planned home and hospital births in South Australia, 1991e2006: differences in outcomes. Med J Aust 2010;192:76-80. 30. Bastian H, Keirse MJ, Lancaster PA. Perinatal death associated with planned home birth in Australia: population based study. BMJ 1998;317:384-8. 31. Northam S, Polanovich S, Restrepo E. Birth certificate methods in five hospitals. Public Health Nursing 2003;20:318-27. 32. Zollinger TW, Przybylski MJ, Gamache RE. Reliability of Indiana birth certificate data
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compared to medical records. Ann Epidemiol 2006;16:1-10. 33. Northam S, Knapp TR. The reliability and validity of birth certificates. J Obstet Gynecol Neonatal Nurs 2006;35:3-12. 34. DiGiuseppe DL, Aron DC, Ranbom L, Harper DL, Rosenthal GE. Reliability of birth certificate data: a multi-hospital comparison to medical records information. Matern Child Health J 2002;6:169-79. 35. Vinikoor LC, Messer LC, Laraia BA, Kaufman JS. Reliability of variables on the North Carolina birth certificate: a comparison with directly queried values from a cohort study. Paediatr Perinat Epidemiol 2010;24:102-12.
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Perinatal risks of planned home births in the United States Amos Gru¨nebaum, MD; Laurence B. McCullough, PhD; Robert L. Brent, MD, PhD, DSc (Hon); Birgit Arabin, MD; Malcolm I. Levene, MD, FRCP, FRCPH; Frank A. Chervenak, MD OBJECTIVE: We analyzed the perinatal risks of midwife-attended
planned home births in the United States from 2010 through 2012 and compared them with recommendations from the American College of Obstetricians and Gynecologists (ACOG) and the American Academy of Pediatrics (AAP) for planned home births. STUDY DESIGN: Data from the US Centers for Disease Control and
Prevention’s National Center for Health Statistics birth certificate data files from 2010 through 2012 were utilized to analyze the frequency of certain perinatal risk factors that were associated with planned midwife-attended home births in the United States and compare them with deliveries performed in the hospital by certified nurse midwives. Home birth deliveries attended by others were excluded; only planned home births attended by midwives were included. Hospital deliveries attended by certified nurse midwives served as the reference. Perinatal risk factors were those established by ACOG and AAP. RESULTS: Midwife-attended planned home births in the United States had the following risk factors: breech presentation, 0.74% (odds ratio [OR], 3.19; 95% confidence interval [CI], 2.87e3.56); prior cesarean
delivery, 4.4% (OR, 2.08; 95% CI, 2.0e2.17); twins, 0.64% (OR, 2.06; 95% CI, 1.84e2.31); and gestational age 41 weeks or longer, 28.19% (OR, 1.71; 95% CI, 1.68e1.74). All 4 perinatal risk factors were significantly higher among midwife-attended planned home births when compared with certified nurse midwiveseattended hospital births, and 3 of 4 perinatal risk factors were significantly higher in planned home births attended by noneAmerican Midwifery Certification Board (AMCB)ecertified midwives (other midwives) when compared with home births attended by certified nurse midwives. Among midwife-attended planned home births, 65.7% of midwives did not meet the ACOG and AAP recommendations for certification by the American Midwifery Certification Board. CONCLUSION: At least 30% of midwife-attended planned home births
are not low risk and not within clinical criteria set by ACOG and AAP, and 65.7% of planned home births in the United States are attended by non-AMCB certified midwives, even though both AAP and ACOG state that only AMCB-certified midwives should attend home births. Key words: home birth, midwives, perinatal risks
Cite this article as: Gru¨nebaum A, McCullough LB, Brent RL, et al. Perinatal risks of planned home births in the United States. Am J Obstet Gynecol 2015;212:350.e1-6.
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here has been an increase in home births in the United States over the last 10 years.1 Recent studies have shown that when compared with hospital births, planned home births by midwives are associated with an increase in adverse neonatal outcomes, such as neonatal deaths,2-4 Apgar score of 0, neonatal seizures, or serious neurological dysfunction.5 The American College of Obstetricians and Gynecologists (ACOG) and
the American Academy of Pediatrics (AAP) have concluded that planned hospital births are safer than planned home births, and both professional organizations have also identified clinical criteria for selecting low-risk patients for planned home births.6,7 ACOG and AAP have also stated that midwives attending planned home births should be certified by the American Midwifery Certification Board (AMCB).6,7
From the Department of Obstetrics and Gynecology, Weill Medical College of Cornell University, New York, NY (Drs Grünebaum, Brent, and Chervenak); Center for Medical Ethics and Health Policy, Baylor College of Medicine, Houston, TX (Dr McCullough); Departments of Obstetrics and Gynecology, Thomas Jefferson University, Philadelphia, PA, and Alfred I. DuPont Hospital for Children, Wilmington, DE (Dr Brent); Center for Mother and Child, Philipps University, Marburg, and Clara Angela Foundation, Berlin, Germany (Dr Arabin); and Division of Pediatrics and Child Health, University of Leeds, Leeds, England, UK (Dr Levene). Received Aug. 29, 2014; revised Sept. 9, 2014; accepted Oct. 13, 2014. The authors report no conflict of interest. Corresponding author: Amos Grünebaum, MD. [email protected] 0002-9378/$36.00 ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajog.2014.10.021
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The purpose of this study was to evaluate the frequency of certain perinatal risk factors that were associated with planned midwife-attended home births in the United States from 2010 through 2012 and to compare them with clinical criteria for planned home births established by the ACOG and AAP.
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We utilized data from the National Center for Health Statistics of the US Centers for Disease Control and Prevention (CDC) birth certificate data for 2010e2012, the most recent data available to analyze the 4 ACOG/AAP clinical criteria for planned home births. The CDC files contain detailed information on each of the approximately 4 million births in the United States each year. Data on patient characteristics including birth setting, method of delivery, birth attendant, gestational age, infant birthweight, maternal age, history of
ajog.org prior cesarean delivery, and parity are reported on birth certificates filed each year with each of the states in the United States and compiled by National Center for Health Statistics. These data are publicly accessible on the Internet (http://205.207.175.93/vitalstats/Report Folders/ReportFolders.aspx), where detailed tables can be created and downloaded for further evaluation. According to CDC data, “almost all the home births attended by certified nurse-midwives ⁄certified midwives (98%) or “other” midwives (99%) were planned,”8,9 and therefore, we defined planned home births as births attended at home by midwives. We excluded from planned home births those performed at home by others (eg, family members, emergency medical service, or police, taxi drivers as well as unattended births). Planned US midwife home deliveries for the years 2010e2012, the most recent years available, were analyzed for ACOG and AAP perinatal risk factors that should be excluded from home births7: vaginal breech deliveries, prior cesarean delivery, twin gestations, and postdate pregnancies (gestational age 41 weeks or longer). Hospital births attended by certified nurse midwives served as a reference. Home birtheplanned midwife-attended deliveries were compared with hospital-certified nurse midwives (CNM)eattended deliveries. The CDC database separates midwives into CNM and other midwives. The AMCB certifies 2 kinds of midwives: CNMs and certified midwives (CMs), both of whom have graduated from a midwifery education program accredited by the American Commission for Midwifery Education. The total number of AMCB-certified midwives (CNMs plus CMs) includes only a small percentage of CMs because CMs are permitted to practice in only 5 states. Therefore, the CDC designation of CNMs captures nearly all of AMCBcertified midwives. In addition to CNMs, the CDC also has a designation of other midwives, which includes certified professional midwives, who are not eligible for certification by the AMCB and who have no requirement of a Bachelor’s degree or
Obstetrics graduate training. In addition, the CDC designation of other midwives may include lay midwives and others without any graduate midwifery training. We performed a subanalysis and compared the frequency with which certain perinatal risk factors were associated with home births attended by CNMs with those attended by other midwives (ie, midwives not eligible to get certified by the AMCB). Data were abstracted from the US birth certificate data. Because nonidentifiable data from a publicly available data set were used, this study was not considered human subject research and did not require review by the Institutional Review Board of Weill Medical College of Cornell University. Statistical analyses were conducted for comparisons between planned midwife-attended home births and CNM-attended deliveries in the hospital. Odds ratios and 95% confidence intervals were calculated for each of the 3 provider groups (CNM-attended home birth, other midwife-attended home birth, and CNM-attended hospital birth) and 4 of the risk groups. All statistical analyses were conducted in OpenEpi.10
R ESULTS Between 2010 and 2012, there were a total of 11,905,817 deliveries in the United States, of which 736,070 were attended by CNMs in the hospital. There were 85,318 home births (0.71% of all births in the United States) and after exclusion of 29,178 home birth deliveries performed by others, we included 56,140 deliveries that were attended by midwives at home and are considered planned midwife-attended home births. CNMs attended 19,263 (34.3%) of these home births, whereas other midwives attended 36,877 (65.7%) of planned home births. Table 1 shows the comparisons of perinatal risk factors between deliveries attended in the hospital by CNMs and planned midwife-attended home births by CNMs and other midwives. Of the midwife-attended planned home births, approximately 3 in 10 were at a gestation of 41 weeks or longer, 1 in 156 were
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births with twins, approximately 1 in 23 were vaginal births after cesarean deliveries, and 1 in 135 home births were births with breech presentation. Planned home births attended by CNMs and other midwives had a significantly higher frequency of certain perinatal risks when compared with CNM-attended hospital births. Planned home births attended by noneAMCBcertified other midwives had a significantly higher frequency of perinatal risks for breech presentation, prior cesarean deliveries, and twins, when compared with planned home births attended by CNMs.
C OMMENT The AAP and ACOG previously published policy statements on planned home birth with recommendations when to consider planned home birth, and they listed the use of strict selection criteria for planned home births (Tables 2 and 3).6,7 According to the ACOG, selection criteria for home births include singletons, cephalic pregnancies between 37 and 41 weeks, no prior cesarean deliveries, and certified midwives or physicians as birth attendants. This study shows that 1 in 156 of midwife-attended planned home births (0.64%) were twin pregnancies, even though the ACOG considers twins a contraindication for home births because there is no adequate fetal monitoring, no experienced team, and no ultrasound available in home births.6,7 Studies on the safety of home births from Canada, England, and The Netherlands excluded twins as candidates for home birth because of increased risks.11-14 Even within hospitals, delivery of the second twin, especially when not engaged or nonvertex, requires an experienced obstetrician to prevent perinatal morbidity or even mortality.15 We note that our data indicate that in some hospitals there were apparently CNM deliveries of twin and breech-presentation pregnancies. The data in this study show that 1 in 135 of planned home births attended by midwives (0.74%) were vaginal breech deliveries. Breech vaginal birth is associated with significantly increased risks.
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1.08 (1.01e1.14)
1.03 (0.99e1.06)
1.44 (1.39e1.5)
1.73 (1.69e1.77)
1.34 (1.28e1.41)
1.67 (1.62e1.73)
1.41 (1.37e1.45)
1.71 (1.68e1.74)
9.73 (3567) 9.08 (1744) 6.91 (50,848) Postdates 42 wks
27.7 (5320)
CI, confidence interval; CNM, certified nurse midwife; MW, midwife; OR, odds ratio.
18.59 (136,729) Postdates 41 wks
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Grünebaum. Perinatal risks of planned US home births. Am J Obstet Gynecol 2015.
9.5 (5311)
28.19 (15,755) 28.45 (10,435)
1.33 (1.05e1.67) 2.25 (1.98e2.57) 1.7 (1.39e2.08) 2.06 (1.84e2.31) 0.64 (357) 0.52 (101) 0.31 (2276) Twins
0.69 (256)
1.15 (1.06e1.26) 2.25 (2.14e2.37) 1.93 (1.8e2.08) 2.08 (2.0e2.17) 4.4 (2463) Prior cesarean delivery
3.99 (767) 2.11 (15,455)
Vaginal breech
4.6 (1696)
3.49 (3.08e3.94) 2.64 (2.19e3.18) 3.19 (2.87e3.56) 0.74 (416) 0.23 (1716)
Risk factor
0.61 (118)
CNM-attended (n [ 736,070), % (n)
0.81 (298)
Other MWattended home births vs CNMattended hospital births, OR (95% CI) CNM-attended home births vs CNM-attended hospital births, OR (95% CI) MW-attended home births vs CNM-attended hospital births, OR (95% CI) All MWattended (n [ 56,140), % (n) CNMattended (n [ 19,263), % (n)
Other MWattended (n [ 36,877), % (n) Home births Hospital births
Perinatal risk factors: CNM-attended hospital births vs midwife-attended home births
TABLE 1
1.32 (1.07e1.64)
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Other MWattended home births vs CNMattended home births, OR (95% CI)
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Since the publication of the Term Breech Trial, clinical practices changed around the world, increasing cesarean deliveries for breech births.16 The ACOG recommends that planned vaginal breech births should be done only under hospital-specific protocol guidelines.17 Azria et al18 recommended that a trial for vaginal births in breech presentations should be attempted only with continuous electronic fetal heart rate monitoring and the presence of ultrasound during labor and delivery. Neither electronic fetal heart rate monitoring nor ultrasound is available in home births. Janssen et al11 from Canada and the Home Birth in England Study12 excluded breech presentations from their home birth eligibility requirements. Therefore, it is not surprising that the Midwives Alliance of North America study of planned home births reported an intrapartum death rate of 13.51 per 1000 and a 9.16 per 1000 neonatal mortality rate in breech presentations.19 When compared with the neonatal death rates from hospital deliveries,2-4 these adverse neonatal outcomes are significantly increased. The ACOG and AAP criteria for home births specifically exclude pregnancies 41 weeks or longer from their home birth eligibility.6,7 In this study, 28.19% of home births were 41 weeks or longer. Postterm pregnancies are associated with multiple, well-known complications, such as labor dystocia, increased perinatal mortality rate, low umbilical artery pH levels at delivery, low 5 minute Apgar scores, postmaturity syndrome, fetal distress, cephalo-pelvic disproportion, postpartum hemorrhage, and an increased risk of neonatal death within the first year of life.20,21 A trial of labor after prior cesarean delivery (TOLAC) is associated with a greater perinatal risk than is elective repeat cesarean delivery without labor. TOLACs have an overall small but significantly increased risk of uterine rupture with often catastrophic consequences to mother and/or fetus.22,23 This study showed that nearly 1 in 23 midwife-attended home births (n ¼ 2463, 4.4%) had a home vaginal birth after prior cesarean delivery (VBAC) in
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TABLE 2
Planned home birth: recommendations when considering planned home birth Candidates for home delivery Absence of preexisting maternal disease Absence of significant disease occurring during the pregnancy A singleton fetus estimated to be appropriate for gestational age A cephalic presentation A gestation of 37 to less than 41 completed weeks of pregnancy Labor that is spontaneous or induced as an outpatient A mother who has not been referred from another hospital Systems needed to support planned home birth The availability of a certified nurse midwife, certified midwife, or physician practicing within an integrated and regulated health system Attendance by at least 1 appropriately trained individual (see text) whose primary responsibility is the care of the newborn infant Ready access to consultation Assurance of safe and timely transport to a nearby hospital with a preexisting arrangement for such transfers Adapted from American Academy of Pediatrics.6 Grünebaum. Perinatal risks of planned US home births. Am J Obstet Gynecol 2015.
spite of the fact that ACOG considers prior cesarean section an absolute contraindication to planned home birth.7 TOLACs at home births are even more worrisome, considering the increase in VBACs in home births.24 The recent Midwives Alliance of North America study showed a very high 2.85 per 1000 intrapartum fetal death rate with VBACs.19 The ACOG and AAP recommend that only midwives certified by the AMCB should attend home births.6,7 Nevertheless, this study shows that approximately 2 of 3 planned home births were performed by non-AMCB-certified midwives. Professional organizations like the ACOG and AAP should respond to these findings by continuing to
support collaborative practices in the hospital between physicians and AMCBcertified midwives and strive for a hospital birth that resembles more closely a home birth environment.25 Selection of patients for home births by countries with midwife organizations, such as the Royal Dutch Organisation of Midwives, follows collaborative guidelines with strict protocols for selecting patients for home births.26 The American College of Nurse Midwives has not established midwife-generated guidelines of patient selection for home births in the United States saying that “. guidelines would impact [midwives’] autonomy” and “guidelines might not support midwives if they choose to attend the home birth of a woman with a
breech presentation or a twin gestation or a woman who desires a trial of labor after a previous cesarean.”27 It is possible that some pregnant women with risk factors may insist on home births despite the increased risks of adverse outcomes. In circumstances in which home births are contraindicated because of risk factors, physicians and midwives have the professional responsibility to strongly recommend for hospital birth, to recommend against home births, and to refuse the woman’s request to attend their home birth. This is because patients’ requests by themselves do not determine professional responsibility.28 Kennare et al29 and Bastian et al30 showed that the increase in neonatal
TABLE 3
ACOG Statement on planned home birth (ACOG 2011) Recent cohort studies reporting lower perinatal mortality rates with planned home birth describe the use of strict selection criteria for appropriate candidates. These criteria include the absence of any preexisting maternal disease, the absence of significant disease arising during the pregnancy, a singleton fetus, a cephalic presentation, gestational age greater than 36 weeks and less than 41 completed weeks of pregnancy, labor that is spontaneous or induced as an outpatient, and that the patient has not been transferred from another referring hospital. Trial of labor after cesarean should be undertaken only in facilities with staff immediately available to provide emergency care. The American College of Obstetricians and Gynecologists’ Committee on Obstetric Practice considers a prior cesarean delivery to be an absolute contraindication to planned home birth. Ready access to consultation and assurance of safe and timely transport to nearby hospitals are critical to reducing perinatal mortality rates and achieving favorable home birth outcomes. Availability of a certified nurse midwife, certified midwife, or physician practicing within an integrated and regulated health system. For quality and safety reasons, the American College of Obstetricians and Gynecologists does not support the provision of care by lay midwives who are not certified by the American Midwifery Certification Board. Adapted from ACOG Committee.7 Grünebaum. Perinatal risks of planned US home births. Am J Obstet Gynecol 2015.
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mortality in planned home births was associated with a poor selection of candidates for home births. Our findings of increased perinatal risks among US midwife-attended planned home births may partially explain reports that show preventable increased adverse outcomes such as increased neonatal mortality rates, low Apgar scores, neonatal seizures, and serious neurological dysfunction among US midwifeattended planned home births.2-5 The strength of this study is that the CDC data are nationally comprehensive. No comparable database exists. A limitation of the results is that the actual number of patients with increased perinatal risks in home births is possibly higher than reported here because patients transferred prior to delivery from a planned home birth to the hospital are counted in the CDC birthing data as hospital births and not home births. Other limitations in this study include concerns that have been expressed about the quality of certain data collected in birth certificates, especially those that address maternal health behaviors or certain medical and obstetric conditions (eg, anemia, gestational diabetes, pregnancy-induced hypertension, concurrent illnesses, congenital anomalies, and comorbidities).31-34 These data elements were not used in our study. Our study used data elements found to be a good source of reliable information in birth certificates and that were validated such as place of births, gestational weeks, presentation, history of prior cesarean delivery, and multiple births.34,35
Conclusion This study demonstrates that many midwife-attended planned home births in the United States do not have low perinatal risks but include readily identifiable prenatal risks such as breech presentation, twins, patients with prior cesarean deliveries, and postdate pregnancies. These risks as well as other perinatal risks are known to be associated with increased adverse birth outcomes and are therefore listed by the ACOG and AAP as contraindications for planned home births. In addition, about two-thirds of planned midwife-attended
home births in the United States are attended by noneAMCB-certified midwives. Our study also shows that planned home births attended by midwives not certified by the AMCB have a higher frequency of perinatal risks than planned home births attended by AMCB-certified nurse midwives. REFERENCES 1. MacDorman MF, Mathews TJ, Declercq E. Trends in out-of-hospital births in the United States, 1990e2012. NCHS Data Brief no. 144, March, 2014. Hyattsville MD: National Center for Health Statistics. 2. Grünebaum A, McCullough LB, Sapra KJ, et al. Early and total neonatal mortality in relation to birth setting in the United States, 2006e2009. Am J Obstet Gynecol 2014;211:390.e1-7. 3. Cheng YW, Snowden JM, King TL, Caughey AB. Selected perinatal outcomes associated with planned home births in the United States. Am J Obstet Gynecol 2013;209: 325.e1-8. 4. Wax JR, Lucas FL, Lamont M, Cartin A, Blackstone J. Maternal and newborn outcomes in planned home birth vs planned hospital births: a metaanalysis. Am J Obstet Gynecol 2010;203: 243.e1-8. 5. Grünebaum A, McCullough LB, Sapra KJ, et al. Apgar score of zero at five minutes and neonatal seizures or serious neurologic dysfunction in relation to birth setting. Am J Obstet Gynecol 2013;209:323.e1-6. 6. American Academy of Pediatrics. Policy statement on planned home birth. Pediatrics 2013;131:1016-20. 7. American College of Obstetricians and Gynecologists. Planned home birth. Committee Opinion no. 476. ACOG Committee on Obstetric Practice. Obstet Gynecol 2011;117(2 Pt 1): 425-8. 8. National Center for Health Statistics. Vital statistics data available online: birth data files. Available at: http://www.cdc.gov/nchs/data_ access/VitalStatsOnline.htm. Accessed Aug. 28, 2014. 9. MacDorman MF, Declerq E, Mathews TJ. United States Home Births Increase 20 Percent from 2004 to 2008. Birth 2011;38:185-90. 10. Dean AG, Sullivan KM, Soe MM. OpenEpi: open source epidemiologic statistics for public health, version 2.3.1. Updated June 23, 2011. Available at: www.OpenEpi.com. Accessed June 1, 2014. 11. Janssen PA, Saxell L, Page LA, Klein MC, Liston RM, Lee SK. Outcomes of planned home birth with registered midwife versus planned hospital birth with midwife or physician. CMAJ 2009;181:377-83. 12. Brocklehurst P, Hardy P, Hollowell J, et al. Perinatal and maternal outcomes by planned place of birth for healthy women with low risk pregnancies: the Birthplace in England national
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